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Sediments from cryoconite holes and dirt cones on the surface of Svalbard glaciers:main chemical and physicochemical properties

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Acta Geochimica 2023年第2期42卷 346-359页

作者： Timur Nizamutdinov Bulat Mavlyudov Vyacheslav Polyakov Evgeny Abakumov Department of Applied Ecology Faculty of BiologySt.Petersburg State University16th Liniya V.O.29St.PetersburgRussia 199178 Russian Academy of Sciences Institute of GeographyMoscowRussia 119017

The paper discussed the influence of the forms of sediment accumulation on the surface of glaciers on their chemical and physicochemical *** materials sampled from the surface of five glaciers of the Svalbard Archipelago was *** st.died such forms of sediment accumulation as dirt cones-the ice core covered with sediments and cryoconite holes-hollows on the glacier surface containing cryoconite *** such as total organic carbon content,microbiological activity,pH,the content of mobile forms of potassium and phosphorus,and concentrations of heavy and trace metals were ***,mesomorphological st.dies were carried out and the polydisperse composition of the sediments was *** to the results of this work,it was found that the content of organic carbon in the material selected from dirt cones and cryoconite holes can be up to 2.5%,but the content of clay particles in it is mainly at the 10–15%*** concentrations are up to 250 mg/kg,and phosphorus is up to 800 mg/*** content of metals is typical or lower than in the previously published *** main influence on the chemical composition of materials has a geographical factor of the sampling site,rather than the form of material accumulation.

关键词： Arctic Soil-like bodies Glacier sediments Accumulation

Quantum Conductance st.ircase of Edge Hole Channels in Silicon Quantum Wells

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Journal of Modern Physics 2012年第11期3卷 1771-1775页

作者： Nikolay T. Bagraev Leonid E. Klyachkin Andrei A. Kudryavtsev Anna M. Malyarenko Ioffe Physical Technical institute St. Petersburg Russia

We present the findings for the quantum conductance st.ircase of holes that is caused by the edge channels in the ultra-shallow p-type silicon quantum well (Si-QW), 2 nm, confined by the δ-barriers heavily doped with boron on the n-type Si (100) surface. This longitudinal quantum conductance st.ircase, Gxx, is revealed by the voltage applied to the Hall contacts, Vxy, to a maximum of 4e2/h. In addition to the st.ndard plateau, 2e2/h, the variations of the Vxy voltage appear to exhibit the fractional forms of the quantum conductance st.ircase with the plateaus and st.ps that bring into correlation respectively with the odd and even fractional values.

关键词： Quantum Conductance st.ircase Edge Channels Silicon Nanosandwich Odd and Even Fractional Values

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鸟类对欧亚地区高山生活的适应(英文)

动物学报 2004年第6期50卷 970-977页

作者： Roald L. POTAPOV Zoological institute Russian Academy of Sciences St. Petersburg Russia

欧亚地区高地鸟类区系的贫乏性 (仅有 75种繁殖于林线之上 )受严酷的自然条件和食物资源短缺所决定。适合这些条件的主要适应是飞行模式 ,包括与之有关的形态特征 ,繁殖时间的选择 ,最优化利用微生境和伪装的巢址选择 ,窝卵数的限制 ,... 详细信息

欧亚地区高地鸟类区系的贫乏性 (仅有 75种繁殖于林线之上 )受严酷的自然条件和食物资源短缺所决定。适合这些条件的主要适应是飞行模式 ,包括与之有关的形态特征 ,繁殖时间的选择 ,最优化利用微生境和伪装的巢址选择 ,窝卵数的限制 ,对雏鸟的食物转运模式 ,防护强紫外线辐射和大气干燥。

关键词：鸟类区系巢址选择窝卵数微生境雏鸟生活史特征动物学繁殖时间高山形态特征

Long-Term Trends of Carbon Monoxide Total Columnar Amount in Urban Areas and Background Regions:Ground-and Satellite-based Spectroscopic Measurements

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Advances in Atmospheric Sciences 2018年第7期35卷 785-795页

作者： Pucai WANG N.F.ELANSKY Yu.M.TIMOFEEV Gengchen WANG G.S.GOLITSYN M.V.MAKAROVA V.S.RAKITIN Yu.SHTABKIN A.I.SKOROKHOD E.I.GRECHKO E.V.FOKEEVA A.N.SAFRONOV Liang RAN Ting WANG LAGEO Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China A.M.Obukhov institute of Atmospheric Physics Russian Academy of SciencesMoscow 119017Russia st.petersburg st.te University Saint-Petersburg 198904Russia

A comparative st.dy was carried out to explore carbon monoxide total columnar amount（CO TC） in background and polluted atmosphere, including the st.tions of ZSS（Zvenigorod）, ZOTTO（Central Siberia）, Peterhof, Beijing, and Moscow,during 1998–2014, on the basis of ground-and satellite-based spectroscopic measurements. Interannual variations of CO TC in different regions of Eurasia were obtained from ground-based spectroscopic observations, combined with satellite data from the sensors MOPITT（2001–14）, AIRS（2003–14）, and IASI Met Op-A（2010–13）. A decreasing trend in CO TC（1998–2014） was found at the urban site of Beijing, where CO TC decreased by 1.14% ± 0.87% yr^（-1）. Meanwhile, at the Moscow site, CO TC decreased remarkably by 3.73% ± 0.39% yr^（-1）. In the background regions（ZSS, ZOTTO, Peterhof）, the reduction was 0.9%–1.7% yr^（-1） during the same period. Based on the AIRSv6 satellite data for the period 2003–14, a slight decrease（0.4%–0.6% yr^（-1）） of CO TC was detected over the midlatitudes of Eurasia, while a reduction of 0.9%–1.2% yr^（-1） was found in Southeast.Asia. The degree of correlation between the CO TC derived from satellite products（MOPITTv6 Joint, AIRSv6 and IASI Met Op-A） and ground-based measurements was calculated, revealing significant correlation in unpolluted *** in polluted areas, IASI Met Op-A and AIRSv6 data underest.mated CO TC by a factor of 1.5–2.8. On average, the correlation coefficient between ground-and satellite-based data increased significantly for cases with PBL heights greater than 500 m.

关键词： carbon monoxide trend spectroscopic measurement MOPITT AIRS IASI

Ultraslow Relaxation Process of st.tic Light Scattering Intensity by Boron Oxide above the Glass Transition Temperature

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Journal of Materials Science and Chemical Engineering 2015年第7期3卷 75-80页

作者： N. A. Bokov institute of Silicate Chemist.y Russian Academy of Sciences St. Petersburg Russia

The data describing of the light scattering intensity relaxation above the glass transition temperature by boron oxide obtained by using of the temperature jump methods are presented. It is found that the st.bilization of the glass at 220℃ resulted in increasing of the anisotropic intensity at the same time the isotropic intensity is not practically unchangeable. It is shown that after the temperature jump to 330℃the intensity is characterized by the formation of a maximum. This effect is in compliance with the results obtained for the other oxide glasses. It is est.blished that characterist.c time of the relaxation of the maximum height is about two orders of magnitude more than the st.uctural relaxation time for this temperature.

关键词： st.tic Light Scattering Glass Transition Relaxation Time Boron Oxide

Clinical Value of Molecular Biological Methods in Respiratory Tuberculosis in Children

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Journal of Health Science 2014年第5期2卷 248-251页

作者： Ulia Ovchinnikova Anna st.rshinova Irina Dovgalyuk Natalia Kornev Viacheslav Zhuravlev Department of Phthisiopulmonology St. Petersburg Research Institute of Phthisiopulmonology Ligovskii pr. 2/4 St. Petersburg191036 Russian Federation

The pattern of clinical forms of respiratory tuberculosis in children shows a preponderance of intrathoracic lymph node tuberculosis （89.4%） that is characterized by a complicated process in every third child under present-day conditions. Positive result of PCR closely correlates with the severity and extent of the specific process in children. Real-time PCR （RT-PCR） was ascertain to exhibit the highest.sensitivity in detecting Mycobacterium tuberculosis DNA in children with primary generalized tuberculosis （62.5%） and in those with a disseminated specific process （55.6%）, which was much higher than conventional bacteriological st.dy of diagnost.c materials. By taking into account the findings, the RT-PCR detection of M. tuberculosis was considered as a subst.ntial criterion for evaluating the magnitude of specific changes and the degree of tuberculosis infection activity in children.

关键词： Molecular biological methods, real-time polymerase chain reaction, respiratory tuberculosis, children.

Neutrality Criteria for st.bility Analysis of Dynamical Syst.ms through Lorentz and Rossler Model Problems

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Journal of Applied mathematics and Physics 2015年第5期3卷 569-576页

作者： Evgeniy Perevoznikov Olga Mikhailova st.petersburg st.te University of Trade and economics PetersburgRussia

Two methods of st.bility analysis of syst.ms described by dynamical equations are being considered. They are based on an analysis of eigenvalues spectrum for the evolutionary matrix or the spectral equation and they allow determining the conditions of st.bility and inst.bility, as well as the possibility of chaotic behavior of syst.ms in case of a st.bility loss. The methods are illust.ated for nonlinear Lorenz and Rossler model problems.

关键词： Nonlinear Dynamical Syst.ms st.bility Analysis Methods Dynamical Chaos Lorenz and Rossler Model Problems

Molecular characterist.cs of rifampin and isoniazid resist.nt Mycobacterium tuberculosis st.ains from Beijing,China

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Chinese Medical Journal 2007年第9期120卷 814-819页

作者： JIAO Wei-wei Mokrousov Igor SUN Gui-zhi LI Mo LIU Jia-wen Narvskaya Olga SHEN A-dong Beijing Pediatric institute Beijing Children＇s Hospital Affiliated to Capital Medical University Beijing 100045 China Laboratory of Molecular Microbiology St. Petersburg Pasteur Institute St. Petersburg 197101 Russia Clinical Laboratory Beijing Chest Hospital Beijing 100095 China

Background China is one of the high burden countries of Mycobacterium tuberculosis （TB） infection globally, with high incidence and mortality. We st.died the molecular characterist.cs of rifampin （RIF） and isoniazid （INH） resist.nt Mycobacterium tuberculosis st.ains from Beijing, China, in order to find out the genetic marker for rapid detection of specific drug resist.nce.Methods Forty pansusceptible and 81 resist.nt st.ains of Mycobacterium tuberculosis isolated from Beijing, China during 2002-2005 were analyzed. The modified rifampin oligonucleotide （RIFO） assay based on reverse line blot hybridization was used to detect mutations in the 81 bp hot-spot region of rpoB gene, which is associated with RIF resist.nce. The INH resist.nce associated genes, regulatory region mab-inhA （-15C/T） and st.uctural gene katG S315T were detected by reverse line blot hybridization and PCR-rest.iction fragment length polymorphism （RFLP） method respectively. All the st.ains were typed by spoligotying and the Beijing genotype was further subdivided by NTF locus analysis. The dist.ibution of drug resist.nce associated mutations in the above genes was compared in these groups. Results Sixty-five （91.5%） of 71 RIF resist.nt and 52 （92.9%） of 56 multidrug-resist.nt （MDR, i.e. resist.nt to at least.RIF and INH） st.ains were found to harbor mutations in the rpoB hot-spot region. No mutation was detected in RIF sensitive st.ains. The specificity and sensitivity of the modified RIFO assay were 100% and 91.5%, respectively, katG315 AGC〉ACC and inhA-15C〉T mutations were found in 40 （60.6%） and 10 （15.2%） of 66 INH resist.nt st.ains, respectively; 7.6% of INH-resist.nt st.ains had mutations in both of these genes. Therefore, a combined use of both katG315 and inhA-15 identified 68.2% of INH-resist.nt st.ains. The Beijing genotype accounted for 91.7% of total st.ains and was further subdivided into ＂modern＂（76.6%） and ＂ancest.al＂（23.4%） group. There is no significant difference between ＂an

关键词： Mycobacterium tuberculosis drug resist.nce rifampin isoniazid

Nonlinear polaritons in a monolayer semiconductor coupled to optical bound st.tes in the continuum

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Light(Science & Applications) 2020年第1期9卷 1480-1487页

作者： Vasily Kravtsov Ekaterina Khest.nova Fedor A.Benimetskiy Tatiana Ivanova Anton K.Samusev Ivan S.Sinev Dmitry Pidgayko Alexey M.Mozharov Ivan S.Mukhin Maksim S.Lozhkin Yuri V.Kapitonov Andrey S.Brichkin Vladimir D.Kulakovskii Ivan A.Shelykh Alexander I.Tartakovskii Paul M.Walker Maurice S.Skolnick Dmitry N.Krizhanovskii Ivan V.Iorsh ITMO University Saint Petersburg 197101Russia st.petersburg Academic University Saint Petersburg 194021Russia Saint petersburg st.te University ul.Ulyanovskaya 1Saint Petersburg 198504Russia institute of Solid st.te Physics RASChernogolovka 142432Russia Science institute University of IcelandDunhagi 3IS-107ReykjavikIceland Department of Physics and Ast.onomy University of SheffieldSheffield S37RHUK

Optical bound st.tes in the continuum(BICs)provide a way to engineer very narrow resonances in photonic *** extended interaction time in these syst.ms is particularly promising for the enhancement of nonlinear optical processes and the development of the next generation of active optical ***,the achievable interaction st.ength is limited by the purely photonic character of optical ***,we mix the optical BIC in a photonic cryst.l slab with excitons in the atomically thin semiconductor MoSe_(2) to form nonlinear exciton-polaritons with a Rabi splitting of 27 meV,exhibiting large interaction-induced spectral *** asymptotic BIC-like suppression of polariton radiation into the far field toward the BIC wavevector,in combination with effective reduction of the excitonic disorder through motional narrowing,results in small polariton linewidths below 3 *** with a st.ongly wavevector-dependent Q-factor,this provides for the enhancement and control of polariton–polariton interactions and the resulting nonlinear optical effects,paving the way toward tuneable BIC-based polaritonic devices for sensing,lasing,and nonlinear optics.

关键词： polar nonlinear continuum